package com.genius.workflow.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

//test
public class MD5 {

	private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d",
			"e", "f" };

	/**
	 * md5加密
	 * 
	 * @param text
	 *            需要加密的文本
	 * @return
	 */
	public static String encode(String text) {
		try {// aes rsa
			MessageDigest md = MessageDigest.getInstance("MD5");
			byte[] result = md.digest(text.getBytes()); // 对文本进行加密
			// b
			// 000000..0000011111111
			StringBuilder sb = new StringBuilder();
			for (byte b : result) {
				int i = b & 0xff; // 取字节的后八位有效值
				String s = Integer.toHexString(i);
				if (s.length() < 2) {
					s = "0" + s;
				}
				sb.append(s);
			}
			// 加密的结果
			return sb.toString();
		} catch (NoSuchAlgorithmException e) {
			// 找不到该算法,一般不会进入这里
			e.printStackTrace();
		} 

		return "";
	}

	public static String MD5Encode(String origin, String charsetname) {
		String resultString = null;
		try {
			resultString = new String(origin);
			MessageDigest md = MessageDigest.getInstance("MD5");
			if (charsetname == null || "".equals(charsetname))
				resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
			else
				resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
		} catch (Exception exception) {

		}
		return resultString;
	}

	private static String byteArrayToHexString(byte b[]) {
		StringBuffer resultSb = new StringBuffer();
		for (int i = 0; i < b.length; i++)
			resultSb.append(byteToHexString(b[i]));

		return resultSb.toString();
	}

	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0)
			n += 256;
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}
}
